The key for me is one real, full day off. No work, no half-day, etc. I've found that not taking any days off is what burns me out more than anything. I probably

The key for me is one real, full day off. No work, no half-day, etc. I've found that not taking any days off is what burns me out more than anything. I probably put in more productive hours taking off one day per week than I did during all those years when I tried working every day as long as coffee would keep me going. I'd like to say that I take off one day every weekend, but that would be a lie. I probably take off one or two Sundays a month, but I do them completely without even responding to work mail, and that seems to be enough. Like the other commenters, though, I also keep up working out. But that's worth doing just to improve your sleep -- I find that the better sleep more than offsets the time spent in the gym.